NIDA InfoFacts: Khat

Health/Behavioral Effects²

The main psychoactive ingredients in khat are cathine and cathinone, chemicals that are structurally similar to, but less potent than, amphetamine, yet result in similar psychomotor stimulant effects. Chewing khat leaves induces a state of euphoria and elation as well as feelings of increased alertness and arousal. The user also experiences an increase in blood pressure and heart rate. The effects begin to subside after about 90 minutes to 3 hours, but can last 24 hours. At the end of a khat session, the user may experience a depressive mood, irritability, loss of appetite, and difficulty sleeping.¹

There are a number of adverse physical effects that have been associated with heavy or long-term use of khat, including tooth decay and periodontal disease; gastrointestinal disorders such as constipation, ulcers, inflammation of the stomach, and increased risk of upper gastrointestinal tumors; and cardiovascular disorders such as irregular heartbeat, decreased blood flow, and myocardial infarction. There is also consistent epidemiologic evidence for a weak association between chronic khat use and mental disorders. Although there is no evidence that khat use causes mental illness, chewing khat leaves may worsen symptoms in patients who have preexisting psychiatric conditions.

It is unclear whether khat causes tolerance, physical dependency, addiction, or withdrawal, but nightmares and slight trembling have been reported several days after ceasing to chew.

Extent of Use

It is estimated that 10 million people worldwide chew khat.² It is commonly found in the southwestern part of the Arabian Peninsula and in East Africa, where it has been used for centuries as part of an established cultural tradition. In one large study in Yemen, 82 percent of men and 43 percent of women reported at least one lifetime* episode of khat use.² Its current use among particular migrant communities in the United States and in Europe has caused alarm among policymakers and health care professionals. No reliable estimates of prevalence in the United States exist.